Dozens dead in Indian highway collapse

A highway overpass being built in north India has collapsed, killing at least 18 people when an immense concrete slab slammed down onto the crowded road below, authorities say.

Five injured people were pulled from the wreckage, police said. Two were seriously hurt.

Local media reports said that four officials from the state construction agency were suspended in the wake of the collapse on Tuesday.

Rescuers and crane operators worked through the night in the city of Varanasi to try to reach all the victims, but more people were still feared trapped beneath the wreckage, which had crushed four cars, motorcycles and a bus.

It was not clear how many people were in the vehicles. The slab appeared to be at least 15 metres long and two metres wide.

"There was sudden rumble and within seconds we saw" the vehicles crushed, local resident Ramesh Kumar Singh said in a telelphone interview. "It took at least a minute for the people around to realize what exactly had happened."

Most of those killed were in vehicles travelling beneath the overpass, said senior police officer P.V. Ramasastry.

India has a long history of construction accidents caused by poor materials and inadequately trained workers.

In 2016, a long stretch of elevated road being built through the city of Calcutta collapsed, killing 26 people and leaving 11 severely injured.

Prime Minister Narendra, whose political home is in Varanasi, said in a tweet that he was "extremely saddened" by the accident. "I pray that the injured recover soon," he wrote.

Varanasi, an ancient temple city on the banks of the Ganges River, is a centre of pilgrimage for Hindus.